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At least 19 recordsLinked to original sources
PubMed1978

Cyclic polyether-protonated organic amine binding: significance in enzymatic and ion transport processes.

The cyclic polyether, 18-crown-6, reacts with protonated amines in methanol to form complexes whose formation constants (log K) decrease in the order NH4+, RNH3+ greater than R2NH2+ greater than R3NH+. In the case of the organic amines, this stability order is identical to the earlier observed permeability sequence for protonated organic amines in glyceryl dioleate bilayers treated with valinomycin, nonactin, or gramicidin, and in bullfrog and rabbit gallbladder membranes. The decrease in log K values in the above series is primarily a result of decreased enthalpy change (deltaH) values, the entropy change (TdeltaS) term being essentially constant for the systems studied.

Amines↗
PubMed2026

In situ product monitoring in heterogeneous reaction of gaseous trimethylamine on Fe2O3/Fe(NO3)3: Effect of environmental factor and particle property.

Gas-particle reactions represent an important atmospheric heterogeneous transformation process for organic amines (OAs). Environmental factors and particle properties may impact the gas-particle reaction products. Although the products from gas-particle reactions can be monitored by various in situ techniques, related data remain scarce. Here, the interfacial and gaseous products from the reaction of trimethylamine on Fe2O3/Fe(NO3)3 particles under light irradiation with mixed NO2, O2, SO2 and H2O were monitored using in-situ diffuse reflectance Fourier transform infrared spectroscopy and proton transfer reaction time-of-flight mass spectrometry. Dark reaction of gaseous trimethylamine on Fe2O3/Fe(NO3)3 generated two interfacial products types: N-containing ones (CH3NCH2, CH3NO2, (CH3)2NCHO, and CH3N(OH)CHO) and N-free ones (alcohols, aldehydes and acids), both accumulating with reaction progression. Light irradiation and O2 oxidation enhanced formation of these products, while NO2 promoted the production of CH3NO2 and (CH3)2NCHO. H2O and SO2 occupied the active sites of particles to inhibit the formation of all products. Compared to Fe(NO3)3, Fe2O3 showed absolute dominance in contribution to the formation of products. Considering the smaller particle size of Fe2O3 and excess Fe(NO3)3, the physical mixing of them reduced the generation of interfacial products. Furthermore, gaseous products of CH3OH, HCHO, CH3CHO, HCOOH and CH3COOH detection clarified the N-free interfacial products. The presence of Fe(NO3)3 inhibited the formation of HCOOH and favored the formation of CH3CHO in the gas phase. By combining product information with thermodynamic calculations, the heterogeneous reaction pathways of trimethylamine were tentatively proposed. These findings provide a guiding significance for the migration of OAs in real atmospheric environment.

Methylamines↗
PubMed1978

[Kinetic and spectral parameters of the amines oxidative N-dealkylation with participation of the liver microsomal cytochrome P-450. Amines oxidation with organic hydroperoxides].

Kinetics of demethylation of a number of amines involving hepatic microsomal cytochrome P-450 and organic hydroperoxides (tret-butyl- and cumylhydroperoxide) have been investigated. Decomposition rate constants for the substrate-cytochrome P-450-ROOH complexes have been determined in a generalized form. Activation parameters, deltaH* and deltaS*, are calculated for decomposition of the complexes. There is a linear relation between deltaH* and deltaS*: deltaH*=18.7 kcal + 333 degrees K deltaS*. Compensation relationship is characterized by the value of alpha=333 degrees K/Taverage=1.11. The nature of the limiting step in the cytochrome P-450-NADPH-O2-system and the cytochrome P-450-ROOH-system is discussed.

Amines↗
PubMed1976

The effect of poly-L-lysine, amiloride and methyl-L-lysine on gill ion transport and permeability in the rainbow trout.

The action of poly-L-lysine (PLL) on Na and Cl transport across freshwater fish gills was studied. Low concentration (10-6M) were added to the external medium for brief periods (1--5 min), then removed. During the next 20 min there was a rapid net loss of Na (117+/17 muEquiv[100 g]-1hr-1) and Cl (129+/17 muEquiv[100 g]-1hr-1). Both values are an order of magnitude larger than unidirectional effluxes in control fish. The efflux of both ions decreased to control values within 60 min after application and removal of PLL. In contrast, unidirectional influxes (JCl in and JNa in) were inhibited by about 40+ and showed no sign of returning to the original rates for 3 hr. Thus, PLL has two independent actions, causing a large increase in gill permeability which is reversible within an hour and apartial inhibition of influx which showed no sign of reversing for 2--3 hr. When PLL was applied for a longer period (60 min, the results were qualitatively similar but the permeability change was larger and persisted longer. These effects were compared with those of the small organic amines, amiloride and methyl-L-lysine. The latter inhibited JNa in, but there was not other similarity to PLL. Neither affected sodium efflux, not did they have any effect on Cl movements, in or out, across the gill. Inhibition of JNa in, was rapidly and completely reversible, and amiloride was shown to act by competing with Na for an entry site.

Amiloride↗
PubMed1979

Dissolution of cystine ureteral calculus by irrigation with tromethamine.

An alternative to surgical intervention in cases of symptomatic cystine calculi is presented. A large obstructing ureteral calculus in a patient who had undergone 4 prior lithotomies was dissolved during a 5-day period by irrigation via a ureteral catheter with tromethamine-E, an alkaline organic amine intravenous solution.

Adult↗
PubMed1975

Synaptic organization of the amine-containing interplexiform cells of the goldfish and Cebus monkey retinas.

Fluorescence microscopy has revealed a new type of amine-containing retinal neuron, the interplexiform cell, that extends processes in both plexiform layers. After intravitreal injection of 5,6-dihydroxytryptamine in goldfish and Cebus monkey, the processes of these cells can be identified by electron microscopy. In goldfish, the processes are pre- and postsynaptic to amacrine cells in the inner plexiform layer and presynaptic to bipolar and horizontal cells in the outer plexiform layer. Interplexiform cells thus provide an intraretinal centrifugal pathway from inner to outer plexiform layers.

Amines↗
PubMed1979

[Biogenic amine content and the pathomorphological shifts in different organs and tissues in a period of the hematogennic spread and fixation of botulin toxin].

In experiments on cats it was shown that 30 minutes after intravenous injection of botulinum toxin, type C, there was a fall in the catecholamine and histamine contents with a simultaneous increase of serotonin in various structures of the brain and spinal cord and in a number of inner organs as well. The metabolic changes in the biogenic amines were combined with certain pathomorphologic changes seen in the form of acute swelling, chromatolysis, destruction of some neurons of the spinal cord and brain, distrophic changes in inner organs, and an increased permeability of the blood-tissue barriers. Marked biochemical and pathomorphologic changes in the spinal cord and brain where the minimum concentration of toxin becomes manifest during its spreading allow a conclusion that botulinum neurotoxin shows its pathogenic action through a disturbed metabolism of biologically active substances.

Animals↗
PubMed1979

Alteration of insulin binding and cytoskeletal organization in cultured fibroblasts by tertiary amine local anesthetics.

Tertiary amine local anesthetics cause a time- and dose-dependent, reversible increase in insulin binding sites in cultured chick embryo fibroblasts. Incubation of fibroblasts with 0.2 mM dibucaine for 3 h at 37 degrees C results in a twofold to threefold increase in insulin binding, with an increase in average number of binding sites (Ka = 3.0 X 10(7) M-1) from 9 X 10(3) per cell. Trypsin or ethyleneglycoltetraacetic acid (EGTA) alone increases insulin binding twofold to threefold, but fails to further increase 125I-insulin binding in cells pretreated with dibucaine. Transformation of chick embryo fibroblasts with Rous sarcoma virus causes a threefold to fivefold increase in insulin binding, which is not further increased by incubation with dibucaine. As demonstrated by transmission electron microscopy, dibucaine and trypsin also induce changes in the cytoskeleton of chick embryo fibroblasts, characterized by disorganization and disappearance of microfilament and microtubule bundles. These alterations are accompanied by gross morphologic changes, including rounding of cells and appearance of numerous ruffles and blebs on the cell surface. These observations are consistent with the hypothesis that expression of surface receptors in cultured chick embryo fibroblasts is related to the organization and disorganization of cytoskeletal structures.

Anesthetics, Local↗
PubMed1976

Carbon-11 labeled aliphatic amines in lung uptake and metabolism studies: potential for dynamic measurements in vivo.

In order to assess the potential utility of amines labeled with short-lived nuclides as agents for lung imaging and function studies in humans, a series of aliphatic amines (C4-C10 and C13) labeled with carbon-11 (T 1/2 = 20.4 minutes), which decays by the emission of body-penetrating radiation, has been used as a model for studying some basic parameters affecting amine uptake and metabolism by the lung and other tissues in mice. The lung uptake (percentage of dose per organ) of aliphatic amines at 1 minute increased from 2.18 +/- 0.13% for butylamine to 13.33 +/- 0.84% for tridecylamine. Partition coefficients (between n-octanol and pH = 7 buffer) were measured for the C4 through C10 amines and for octanoic acid and octanenitrile. Within the amine series, the partition coefficient correlated with lung uptake. A comparison of a series of compounds all having a carbon chain length of eight but with different functional groups (--NH2, --C=N, --CO2H, --OH) showed that the amino group as well as the relatively lipophilic alkyl group were required for lung specificity. The 11C-aliphatic amines were rapidly metabolized via monoamine oxidase (ultimately to 11CO2). Non-amine metabolites in blood and lungs at 5 minutes postinjection were 95 and 50%, respectively. Pretreatment of mice with iproniazid and with pargyline decreased 11CO2 excretion, and iproniazid significantly increased the radioactivity retained by the brain, lungs and liver at 15 minutes. The rate of 11CO2 excretion depended on carbon chain length (C4 less than C5 less than C6 greater than C7 greater than C8 greater than C9 greater than C10 greater than C13).

Amines↗
PubMed1979

[Functional morphology of the adrenergic innervation and adrenocontaining structures of the lymphoid organs].

Topography of adrenergic neural fibres and adrenodependent structures in lymphoid organs of some mammals (rat, cat, dog, guinea-pig, golden hamster) has been studied by means of Falck's method with other histochemical methods applied simultaneously. In thymus, spleen, tonsils, lymph nodes and appendix adrenergic innervation is performed at the expense of adventitial vascular plexus and some neural fibres directed towards the organs' parenchyma. In the parenchyma of the lymphoid organs some fluorescent interfollicular macrophages and intrafollicular cells with serotonin and catecholamines in their cytoplasm were detected spectroscopically. These two types of cells respond differently to increasing amount of free amines in the organism. Orthochromic mast cells and elastic fibres also possess fluoresent properties which are connected with the presence of serotonin and catecholamines in the lymphoid organs.

Adrenergic Fibers↗
PubMed1979

Biogenic amines derived from tryptophan in systemic and cutaneous scleroderma.

Blood levels of serotonin (5-HT) and urinary excretion of 5-hydroxyindole-acetic acid (5-HIAA), tryptamine (T), and indole-acetic acid (IAA) were determined in 39 cases of systemic scleroderma and in 7 cases of very severe cutaneous scleroderma. The T/IAA ratio was normal and serotonin elevated in mild and rather severe acrosclerosis alike, i.e. in systemic scleroderma with pronounced vascular involvement. The T/IAA ratio was increased and serotonin normal in severe acroscleroderma, representing an intermediate form or transition to diffuse scleroderma, in severe diffuse scleroderma, and in severe cutaneous scleroderma. The T/IAA ratio and serotonin level were both elevated in a few cases of systemic scleroderma and in severe generalized morphea with concomitant vascular changes. The findings suggest impaired monoamine oxidase (MAO) activity in scleroderma with consequent accumulation in the organism of biogenic amines derived from tryptophan. An increased T/IAA ratio seems to be of prognostic significance in scleroderma, suggesting an adverse course of the disease.

Colorimetry↗
PubMed1976

[Water pollution and carcinogenic risks].

The main subjects emphasized in this contribution are the following ones: 1 - To investigate the presence of cancerogenic compounds derived directly or by transformations within trophic chains from domestic and industrial effluents. 2 - To evaluate potential cancerogenic health hazards due to polluted a quatic environement. The following substances might be regarded as to be cancerogenic: nitros amins, mycotoxins, complex organic and inorganic compounds and synthetic organicals. Based on epidemiological and epizoonic evidences, as well as human and experimental pathology, the relevant importance of particular group of compounds is evaluated. Presented evaluation is indicating that the water-borne cancerogenesis might be of an important significance. Therefore, the needs for essential increase in relevant research, implemented by advanced methods, which can cope with complexity of ecological processed, are stressed and further efforts recommended.

Animals↗